Mediastinitis after cardiovascular operations: a case-control study of risk factors.
BACKGROUND
An analysis of risk factors for postoperative mediastinitis can lead to a better understanding of the pathogenesis of this complication and to more effective preventive measures.


METHODS
This case-control study of 37 patients and 74 matched controls evaluated 54 potential risk factors.


RESULTS
Nine variables were significantly associated with increased risk of postoperative mediastinitis: total operation time (p = 0.0013), high body-mass index (p = 0.0033), use of beta-adrenergic drugs before the onset of infection (p = 0.0037), long cardiopulmonary bypass time (p = 0.0072), long aortic cross-clamp time (p = 0.0075), presence of diabetes (p = 0.0122), high body weight (p = 0.0130), and use and duration of temporary pacing wires (p = 0.0293 and p = 0.0241 respectively). In a conditional logistic regression analysis, use of beta-adrenergic drugs before the onset of infection (p = 0.0058; odds ratio 19.7; 95% confidence limits, 2.37 and 163.7) and body mass index (p = 0.0082; odds ratio 1.27; 95% confidence limits, 1.06 and 1.52) were independently associated with a significantly increased risk of postoperative mediastinitis.


CONCLUSIONS
Obesity and use of beta-adrenergic drugs, which is indicative of obstructive respiratory problems, were the most important risk factors suggesting that mechanical strain on the sternotomy and sternal instability may precede infection. Targeted preventive measures for these groups could be justified.
Bitkover
C Y
CY
Department of Cardiothoracic Surgery, Karolinska Hospital, Stockholm, Sweden.
Gårdlund
B
B
D000318:Adrenergic beta-Agonists / Q000627:therapeutic use; D000319:Adrenergic beta-Antagonists / Q000627:therapeutic use; D015992:Body Mass Index; D001835:Body Weight; D006348:Cardiac Surgical Procedures; D002315:Cardiopulmonary Bypass; D016022:Case-Control Studies; D048909:Diabetes Complications; D006801:Humans; D008480:Mediastinitis / Q000209:etiology*; D011183:Postoperative Complications; D012307:Risk Factors; D013997:Time Factors
D000318:Adrenergic beta-Agonists; D000319:Adrenergic beta-Antagonists